Automatic drilling control



Aug. 24, 1943. J. c. CONRAD, ErAL I AUTOMATIC DRILLING CONTROL Filed Nov. 3, 1941 2 Sheets-Sheet 2 (I C. Cob 4240 17L. COW/194D Patented Aug. 24, 1943 AUTUMATIC nnnlnnia conrn or.

Joshua C Conrad and Harold L. Conrad, i Oklahoma City, Okla.

Anplication November 3, 1M1, Serial No. 17,639 3 Claims. (01. 188-416) This invention relates towell drilling equipment and it has particular reference to for controlling the braking equipment of the drilling drumof a rotary rig. i

The principal object of the invention is to provide automatic means responsive toxthe weight of a load on the drilling lines to correspondingly control the friction brake of the drilling drum to thereby maintain control of the tools in the well. For example, when the weight on the drill bit increases inthe course of drilling, this factor is instrumental in so actuating the invention'as to efiect automatic depression ofthe brake lever of thedrilling drtun, to stopthe sa'r'ne and cease feeding out line- Conversely, when the bit drills down to decrease the load thereon, the invention; is effective to release the brake of thedrilling apparatus drumtofeed outdrilling "line andthereby increase the'load on the bit. In this manner, uniform andconstant weight isimppsed on the'b withamininum of attention,

Another object of the invention 'is to provide, through the medium of the invention, a safety factor, in that should the, string of pipeseparate;

in the well, the suddenlesseningof weight sup ported by the'dead line will instantly operate the invention to set the brake ,on the drilling drum and hold the remainder of the pipe supported by the drilling line,

Another object of the inventionisto provide in conjunction with-the automatic drilling control, visible means for indicating the weight of the load on the 'clrillingline at all times and by;

which the driller. is 'enabledlto determine the performance of 'the automatic control. Yet another object of the invention is'to provide means for-maintaining true adjustment in thejlineconn'ecting the automatic control with the drilling drum brake lever toinsure simultaneousoperation, of these elements under any andall conditions. r

With the foregoing obj'ectsjas paramount, the invention has, further reference to certain features of accomplishment, ,to become manifest as the description proceeds, taken in connection with the accompanying drawings, wherein:

,Figure 1 is an elevational view'cf a rotary well drilling rig,'w1th the inventionshown thereon Figure 2 is an elevational View of an apparatus'ernbodying the invention. Figure, 3 is a view on line Figure 4 is a view on line L-d on Figure 2. Figure5 is amodified formof apparatusserving in the capacity of that shown in Figure2.

Figure 6 is a 3-3 on Figure 2.

detail view of a device forretaim' the brake line when the drilling controltapparatus is not inuse.

vention. I 7

Figure 8 is a front elevational View or" the device shown inlFigure '7. v

Figure 9 is yet anotherlniodification oi the structure shown in Figures 2 and 7, and

Figure 10 is a plan View of the device shown in Figure 9.. v Continuing with a more detailed description of the drawings, reference is primarily made-to Figure 1 wherein is, shown a derrick E9 of conventional construction, as well'as .a rotary table H and drawworks l2 The usual drilling drum i3 is'shown in connection with the draw works, having a brake drum Hi and a brake operating lever 15. Conventional also is the swivel l6, kelly I1, traveling block l8, orcwn,block'i9, dead line '26] and drilling line [2i which-latter is threaded, in'the usual manner over the crown block 19, through the traveling block it, thence ,over the crown blocl; from-,ivhich it extends downward to the drum I3 and In drilling, ,the driller attends the drum wound thereupon.

manipulating the drum by means of the lever l5;

This operation has been heretofore accomplished manually and requires the undivided attention- ,of a highly skilled operator at all times, whose workdepends' largely upon experience, enabling himfto' feel the action of the drum, in. the

absenceof visible means and automatic equip-. "3. ment to aid in the operation of the drilling drum and its' effect upon the'line. 1

The. invention lessens materially the responsibilities of the driller and at the same time reduces his labor, yet improving uponthe accuracy of his efiorts by providing automatic means for controllingnthe movement of the drilling drum. Accordingly, the invention consists of a frame '22 (Figs. 2, Band 4), to one end of which is rigidly connected an obtuse angular'arm 23. This arm is constructed-so that one plane thereof is attachable, by means of U -bolt 24 to the dead line 2c, the meeting point a (Fig. 2) oithe planes of the arm determining one bend in the cable 2i! while the point of connection of the latter to the arm by the U-bolt, determines another bend therein. The object iswto provide three be'ndsin the dead line and to utilize the force tending to straighten the line for useful work, which, in the present case, is to compress the coiled spring 25, disposed in the frame 22, for

the purposes to be hereinafter set forth.

"feeding out the line Zl'as the bit descends and underwhich it operates.

Extending axially through the frame 22 and to rise, due to spring 5, relieving the friction on sprin 25 is a rod 28. The spring 25 is interthe brake drum l4 and slacking off on the drillposed between a plate 21, affixed in the frame ing line 2|. However, this action is only monear one end thereof and a collar 23 mounted me tary d t e b ake e s a ain placed on the rod. The collar 28 i held against moveunder tension as soon as the drill bit again asment by nut 29 but is adjustable to vary the sumes the allotted Weight of the load, which retension on the spring 25. sults in a slackening 0f thedead line 29. Ob- V The o osite end of the rod 26 carries a yoke viously, this slackening of the deadline willre- 30, in which is mounted a grooved roller 3!, 'lieve tension on thespring 25candallow it to' against which the line 20 is passed. It i apparexpand, causing the arm 32 to move away from ent therefore that any tensile strain imposed on the ad ne, unW ndl g the chain 39 On the the line 20 will have a tendency to straighten k t rotating the latter counter-clockwise,

th tt and t for t created 111 cause i to similarly rotate the sheave 38. The brake line the rod 25 to move axially coward the cable, s herefore wo nd n the sh av akin up compressing th spring 25, slack therein and urging the brake lever I 5 down- Mounted on'and extending at right angles to Wa d o hereby set the brake and prevent fur- I the rod 26 is an arm 3:, reinforced by websas ther' nw n of drilling line. s, ac n .i

and held in adjustable position on the rod 25 repeated as drilling e nd the We ght b t 34, thr d d on th d o t (mp0- variations are indicated on the dial of the tensite end of the frame 22 are mounted bearings t fis, Of thet 35, spaced apart. A shaft 36 is journaled in nt 2 0 c these bearings and a sprocket Wheel 7' 'It is apparent also from the foregoing that;

ype described in U. S. Letters mounted thereon midway between its ends. A e t String of P in the b es i wo sheave 38 isfmounted on one end of the shaft for any reason: the t n' l 92 16 58 t set i outside of the frame. 22. A sprocket chainv 39 the a e'on the drilling drum. This 1, e f ed has one end secured to the arm 32 and is passed y th li d lessening f Weight 9n h d over the sprocket wheels S'I'tc gembraceia portion a w e th sp g 25 t e a d, tak gup, of its toothed periphery and is secured thereto slack nt e b e e' l thereby q nathei at b (Fig. 2). 7 brake lever downward to'operate the brak e .'I 'his V Lying in the groove of the sheave-ea: and sur- Would a b true i ahycase causin undue munding a part of its periphery s a linei io, aq e ne f the load uspendinglines; I w i one end of which is aflixed to the periphery of s Flgul'e 5 ws 9! s sh vm e ii rm-e he thejsheave at c. This line which will behereinstructure J described e n i ee i h after referred to as the brake linefflfor clarity; device a the r su t a h e a e en a 'b t V extends downward from the 'p'ositio of th s. 5 h g 'structure differs in at abell crank.,. v p ratus on the dead line 20, through the derrick SPODdS to varlations in the degree of ten;

floor, under a sheave 4|, across underneath the Sion n h e to vary. the tension on the. A fioorj under another sheave 42, upward through brake 11 5 i l the derrick floor and is att'achedQ-as showirin I In t r tur thefr'ame zlrrs r i s the. Figure 1,'t0 fthec handle of the brake leveril5. coiled jsp 2 ",t ou ?w h-e t ds th Asdevice g3 provides the actual cqnnection strain ro'd 23a, the latter being provided with a tweenthe brakeline'ahd lever l5, and, through Y androller 24a 0 eae f ad. 11, 2 7 I the medium of a threaded rod and crank it 7 i -F th described e see h bb ufi f-i a meansyfor'adjusting the tension on this line angular m her 26%, by re on i tsthree points, is fi t d V I g c i j of engagement with the cable, places the required It will beu derst od that the showin ill Fig deflection in th m r o p es spri fia comprehension and that th inventioninayhe 01 Cable? located in'positions'best suited for the conditions a ure 1, is more oricss diagrammatic for. b e tter cs n withthejdesreeof ten impesed 5 '9 means e i e tean'a mizfia; 'Iniop'eration, the machine. is clamped to the secured to n extending outward'fro nthe strain dead line 20 in the manner shown, and thejbralge. 1 3 The Opposite arm otthefbellicrankf 1 line threaded under sheaves 4|: and 42 and (1011- is J' 0 On n of the bl'a qjlinefiigl the. nected to.the brake lever is. The crank fifi is latter x d ng downward unde i eaves-fifiw [One arm of the'b ell'cranlr ltais rotated toimpose just the. right amountoften a11d upward through the 'fioori.of the derrick. sionv Qnthe brake line 40 and with other factors 0bv1011sIy, n the ad 1in -25cissubjectedin'prpper relativeadjustment; drilling'isstarted, to tensil t t Sp 2a is compressed, 5

Presuminggthat the a i um load is 1100,00o" a s bell cr 20a temove n ts pi ot a p un s and the driller desires 'to' impose'idcoo o -w s r t A c y ehr e e J 7' po nds h the drill bit. The t mp rew or; 29a s a k e tth'e sla kis-taken up by 'upf- I tension adjuster 4G is mani ulated t ll ward movement of the brake leveril,5 whichiis the difference etween the actual weightof the caufied to Q by pr S, (Fig. 1).; When full load and that assumed by the bit. The i H h the dead line 25a is relieved, spring tensiometer ss' (Figure 1)-mo'un ted oh the dead pa ds, rotating the'bell cranlr'zpd in the line at above the automatic control, 'will show. 6 Opposite direction tensioning b ake linalfiafa d ,00Q pounds, indicatingto the driller that 10,000 Setting brake; l ver 1.5.

poun s of weight rests on cthe bit. The inven- Figure 6 s a es a tensioning deviceioiithe tion,'being adjusted to requirements, willallow brake line which may be suhstitutedjjor that,

' the drilling drum It to operate until the bit has shown in Figure 1 and the brake line, forfthe reachedjsuchdent A the bit progresses, the ten ion onlithe, 'ac r f reference 2911, employed.todenotethe deadline, whichcarries the load increasescaus a e l ne in Figure 5, justdescr bed Thisteriing. the rod 26 to move axially to ompress the qningjdevice also serves to retain the-brake line I spring 25; This action-result in a slackening during'periods whennot in-use, The device'conr y of the brake line 40, allowing the brake lever l 5 sists of apipe 3m,

'slotted'on one s ide-tojreceive as'to decrease the load there- 7 sake of clarity, is'identified by the sgmg lghaj i a roller 32a as a guide-for theline 29a, passing upward through the pipe am. A'collar 33 rests on the upper end of the pipeand is received by the lower end of a spring 34a. Another collar 35a rests on the upper end of the spring SAa and is concaved to receive the rounded end of the lower portion of a frame 38a which latter receives the handle of lever l5. A screwrod 31a, manipulated by crank 38a holds the frame in position on lever i511 and also may be manipulated to vary the tension on line 29a. When not in use, the'device, by reason of a hinge 38a, connecting pipe 3 la, to the derrick floor is released from the brake lever i and moved to a horizontal position on the floor below the lever l5. V I v In Figures? and 8 a further modified form of the invention is shown. This modified form consists of a closed housing 41 which, in the present case, is square in transverse section-and extend ing axially through this housing is a shaft or rod t8. Connected by bolts '59 to the lower end of the housing 31 is a small, closed cylinder 50 into which the lower end of rod d8 extends and carries a pistonhead 5i thereon, ground to conform closely to the walls of the cylinderiill. This cylinder contains a quantity of oil and the resistance thereof to movements of the piston head and consequently the rod 3$, affords a means to absorb shocks resulting from sudden jerks imposed on the cable. f v

Surroundingthe rod Ml, interiorly of the housing 41 is a coiled spring 52 having considerable compressive resistance. One end of the spring bears against a flanged collar 53 at the top while the lower end of the spring bears against a similar flanged collar 54, the latter being secured adjustably on the rod by means of nuts 55. These nuts are likewise employed to hold one end ofan arm 55 which extends outwardly at right-angles from the rod 68, through a slot 51 in the housing and to which reference will again be made presently. a 4

Also carried by the rod 48 is a guide member 58, shaped to conform to the walls of the housing 41. This member is ground to a close fit in the housing and augments the shock absorbing action of the piston head '5! in the small'cylinder therebelow. V

Mounted ontop of the housing e! is a bracket bearing 59. Journaled in this bearing is a pin inthe cable opposite the fulcrum point 681 of the member 6 I. These variations influence the member 5| to rock on its fulcrum the spring 52 is either compressed or expanded by movements of the rod 48.

Connected to the outer end of the arm 56 is a sprocket chain 68 which latter extends over a part of the periphery of a sprocket wheel 69. The sprocket Wheel 69 is mounted on a stub shaft it which also carries an annularly grooved sheave Ht 1 It'is apparent that when a load is imposed on the cable 66 sufficient to overcome the resistance of spring 52, the member 6! will move in a counter-clockwise direction on its fulcrum, urging the rod is upward and compressing spring 52. Simultaneously, the slot 51, allowing sprocket wheel 69.

Wound on the sheave ii is a line '12. This line extends downward under asheave l3 thence under-a similar sheave M and upward toa point of connection to a tensioning member i5 which latter, in turn, is connected to the handle of the brake lever it, shown fragmentarily in Figure-'2.

the chain 68 to wind on the Reference to the tensioning member will again be made presently.

69, providing a fulcrumrfor an angular member 6 i. This member, as apparent in Figure '7 is comand transverse to its longitudinal axis to provide two portions on different planes. One plane thereof has an aperture to receive the upper end prised of a plate bent on a line midway between v of the rod (48 which latter carries a half-round Y nut 62, against which bears lock nuts 83. The aperture is countersunk to conformably receive the half-round nut 62 since the member 6| is movable on its fulcrum 6o for the purpose to be later explained. The other plane of the member ii! has pairs of holes (54 therein to selectively receive a U-bolt E5.

The U-bolt embraces the cable or dead line 66, which passes downward axially along the housing ,'l, under a grooved roller. 61, mounted on the housing near its lower end. In passing over the fulcrum. point of member iii, a bend is placed in the cable and it is through the offices of the three points of engagement with the cable that the invention is operated to obtain the result expected. 7

Variations in the weight of loads carried by the cable correspondingly vary the degree of bend use, such as in It will be understood is held'in inoperative position by means of a spring such as S in Figure 1, since the brake mechanism is of conventional and well known construction. This being true, the normal movement of the brake lever, under the influence of its spring action, exerts a pullon the line it, which will, as in the previouscase, be referred to as the brake line. This pull will take up slack in the brake line caused Therefore, it will be seen that as the line E35 which supports the full load of equipment is placed under tension, the resulting action will be the releasing of the brake on thedrilling drum (not shown) to allow the same to feed out more line. Conversely, when the line @5 is relieved of a part of, its load, themember 55 moves in a clockwise direction under the expanding influence of spring 5 2, which action moves the rod ii: and consequently the arm 53 downwardly to unwind the chain 53 from sprocket wheel as. This action places the brake line 1?. under tension and consequently forces the brake lever lii'downward to apply the brake and thereby stop the drilling drum.

, The tensioning device for the brake line i2 is shown in Figure 8 and is identical to its counterpart shown in Figure 6. It consists of of a ball and socket to allow freedom of moveso that it may adjust itself ment of the frame to the movements of the brake lever 15. A screw rod 89, manipulated by a crank Bea. holds the tensioning device on the brake lever and by rotating this screw, tension on the line 12 is increased or diminished.

Moreover, when the tensioning device is not in making trips to change bits or for other purposes, the frame 1.1 is removed and in so doing,

arm 56 is moved in the that the brake lever s by the winding of the chain 88 on the sprocket wheel, as explained.

a frame H. which is received by the handle of the brake I from; the brake lever, and by virtue of the hinged 'pipe 73, the entire assembly may be moved to a horizontal position on the derrick floor, under the brake lever, out of the way, yet maintaining, through spring 79a, moderate tension; on the brake line 12. a

' In Figures 9 and is shown a stillfurther modification of that part of the invention which is attached to the dead line, which latter in this case is indicated by reference character 8 I.

The frame of the machine is comprised of a plateflz having laterally directed portions 83 for a vrod 84 extending the forming bearings length of the plate 82, in parallel relation thereto.

Surrounding the rodrand held between one portion 83 of the plate and an arm 85 on the rod 34 is a coiled spring 85. A yoke 81 is mounted on the forward end of the rod i l and carries a grooved sheave 88; The line 8! lies in the groove of a companion sheave 89, journaled in bearings 90 on the frame and continues downward behind the sheave 88, thence outward over. another sheave 9!. It is apparent therefore that when the line Si is placed under tension, the rod 84 will be forced to the left in Figure 9, compressing the tained being identical to those obtained by the previously described devices. 7 V

- Manifestly, the construction as shown and described is capable of some modification and such modifications as may be construed to fall within the scope and meaning of'the appended claims is also considered to be within the spirit and intent of the invention. i g 7 *What is claimed is; 1. An automatic control for comprising a load carrying line, a frame having an angular arm mounted upon said line for pro ducing a deflection therein variable in relation to the variations in the weight of the load on said line, a spring held normally under compression bythe'tensile rod'extending axially through said DIillE'and actuated, by saidlload line; a stub shaft mounted on and extending at right angles to said frame, a:

sprocket wheel on said shaft, a chain fastenedatoneen-d to: and embracing a portionefsaid wheel I v r with its opposite end connected to said strain rod a friction brake stress imposed on saidline, a strain I whereby to be actuated in accordance with' variations of the load carried by said line, a sheave arrangedfor common rotation with said sprocket wheel and a line connected at one end to "said 7 sheave andv at'its opposite end to the operating lever of said friction brake to' control the move carried by said load line. Y 7

' 2. An automatic control for friction brakes comprising a load supporting line, arframeha'ving a rigid angular arm to Whichsaid line is sements thereof in relation to, the variations in'load cured at two points, a rod axially slidable in said frame under spring tension and connected to said load supporting line to producea bend therein to, effect its movement-in direct relation to variations in tension on said load supporting line, a stuband extending from the'side' ersaid frame, asprocket wheel freely mounted on said shaft, a chain having one end fixedto said sprocket wheel with its opposite also mountedonsaid shaft for rotation by and with'said sprocket, a line connected atone to and, V partially surrounding said sheave'and having its opposite end connected to the lever of .said brake whereby to effect-movement-of said lever in rela -K tion tovariations in the load carried bysaid load: I

supporting line. i

3. In an apparatus for automatically"control:

ling the lever of a friction brake, a load support-- ing line, a frame mounted onsaid, line; a rod mounted axially 'in'said frame and connected fto said 1ine,,a spring embracing and holding said a deflection in said load supporting line, a sprocketwheel mounted,v chain connected at rod under tension to-produce on the side of said frame, a one end to and partially surrounding said sprocket wheel, with its opposite endfixed for movement 7 by and with said rod as changes-in tension on said loadsupporting line occur, a sheave mounted" for rotation with said sprocket Wheel and a line connecting said sprocketand said brake leverto effect movement thereof in accordance with variations in tension on-said loadsupportin line. JOSHUA" C. CONRAD. L

' HAROLD L. CONRAD.

to partially surround the same; 7 end secured to said rod,a sheave 

